Electrical communication wire



Dec. 29, 1959 H. KENMORE ELECTRICAL COMMUNICATION WIRE Filed NOV. 2,1955 IN VEN TOR.

#:zaser [EN/Volta ,lrraelvays United States Patent C) 7 2,918,722ELECTRICAL COMMUNICATION WIRE Herbert'Kenmore; Jersey City, NJ assignor,by mesne assignments, to National'Standard- Company,- Niles, 'Mich.,acorporation of Delaware Application November 2, 1955, Serial No.544,468-- Claims. (Cl. 29 -'183.5)

This invention relates toa strong signal conducting w1re.

Copper wire is ordinarilyemployed for-conducting signals but inthecaseof long distance telephone or telegraph wires copper wire is nolonger employed. desirable to support such wires on poles which arespaced as far apart as possible, and copper wire isnot strong enough tobesupported bywidely spaced poles. result bronze wire, copper coatedsteel wire or galvanized steel wire has been substituted for copperwire.

Of these previously employed substitutes,-steel wire is the mosteconomical and has-very wide usage. Such steel wire'must-have thelowest-possibleresistance to electric current and be as strong as,possible.- However, the best conducting steels are thesteels which arepurest and which have no substantial content of carbon or manganese.Suchysteels have the lowest strength. Manufacwring-processes forproviding steel wires with the ultimate of high strength andconductivity havebeen patented. The balance by which such steel wiresare produced with high strength and relatively. high conductivity isdifficult to maintain and such wire conductors are therefore relativelycostly to produce. Th'ese steel wires have to be galvanizedtoprevent-them'from corroding since they are always used withoutinsulation and are therefore exposed to the elements." b

An object ofthis invention is-to provide a steel wire conductor havinglowelectricalresistivity (compared with steel wire of the same size asnow manufactured and used today, for example) and a very high breakingload;

One phase of this'inventionis based on'the discovery that if a strongsteel wire is first coated with 1-l0%" to 100 g. per kilo) byweight-ofcopper and then with 2-1 5% (20 to 150 g. per kilo) byweightof anadhering coating of zinc, a-superiorconductivity wire for such outdoorvinstallations is provided. The 1-10% of copper is not thick enough byitself to act as a corrosion resistant layer. If copper alone is appliedto obtain corrosion resistance a minimum of 10% by volume or 260 g. per

.kilo or 26% of copper is required. Such an amount of copperwould raisethe cost considerably. The added 245% of zinc produces corrosionresistance at moderate cost. Lead or. aluminum may be substituted forthe zinc. The steel core may be any high strength steel wire, since itis the copper layer which provides the desired conductivity. A strongsteel with a carbon content of .05 to .70% is very satisfactory.Examples of such wire cores are wires made of steels known as C1040 toC1070 (ASTM). The copper is preferably plated onto the steel core. Thetype of plating process disclosed in US. Patent No. 2,680,710 is verysatisfactory but it is preferred to complete the copper and zincelectroplating in one continuous operation. The zinc lead or aluminumlayer is preferably electroplated on top of the copper layer but thislayer can be applied by the hot dip method. The product may be producedin larger size than required in the final product and then drawn down tosize after the plating is complete.

his

As a

Asecondphase of=this-inventionis based on the discovery that theconductivity properties and other properties'of th'eproductoftheinvention can be prevented from deteriorating if :a barrierlayer'of /2 to 5% by weight of nickel isd'eposited betwe'en thezinclayer and the copper. layer.- The barrier layerofnickel prevents thezinc from combining or alloying with thecopper'layer-to produce abrasswhich has-a lowerconductivity than copper;

The invention both as to its organization and its method f of operationtogetherwithadditional objects and advantages thereof will best beunderstood from the following description of specific embodimentsthereof when read in connection withthe accompanying drawing in whichFig. 1 shows a cross-sectional representation of the structure of thewire.

Fig. lA-is -a crosssectional representation of the structure of amodifiedform-of-wiremade according to the invention.

Fig. 2 shows-atypicalmachine forthe production of the product'oftheinvention-in one continuous operation.

In Figure. l, the core 10 is steel andis surrounded bya first concentriclayer 1010f substantially pure copper comprising l-10%' by Weightof-thebody. A concentric layer 102 of zinc, lead oraluminum comprising 210% byweight of the produet'surrounds the copper layer.

Inproducing such awire the core wire 10 of steel, held on bundle 11, ispassed from said bundle 11 and drawn through die 31 by drawing drum 30.Die 31 is slightly smaller than the-smallest diameter of the wire inbundle 11-. Die 31 gives the'wire a work hardened surface. Fromdrum30-the-wire 10 passes to the wire propelling rollers 32 which inthis particular structure push the'wire through straighteningmeans 40over curving or helix forming device 50 which forms the wire into ahelix 10 witha horizontal axis. Thehelix' 10 is stored in its horizontalform on thepairof rotatinglrollers 260, 261.

In this type'of'apparatus it' is very important to maintain the size ofthe individual coils of the helix of uniform size all along the rollers260 ar1d-261. The wire helix is-moved through the apparatus'by thecombination of the pushing force applied at roller 32-and-the rotationalforce applied-by rollers 260 and 261. It hasbeen found necessary toseparately regulate the speed ofthe propelling rollers 32=on'-:theonehand and the forwarding rollers 260 and 261 on the other hand. Rollers32 are rotated by shaft 34driven by gear 35; chain'36, shaft 37 and'speed'regulating device 38. Roller 261 is drivenby chain-265 from roller260. Roller 260 is driven by chain 63, shaft 64 and speed regulatingdevice 65. Speed regulating devices 38 and 65 are shown onlydiagrammatically. Many such devices, Reeves drives for example, areavailable commercially. The shafts which drive these devices 38 and 65are not shown. The speed of the devices 38 and 65 are usually manuallycon trolled and require adjustment from time to time.

Even when the wire is work hardened or tempered there is a limit to thelength of the horizontal supporting and storage roller which can beemployed and still obtain a coil size at the end of the supportingroller which is the same as the coil size at the beginning of suchrollers. For this reason where a plurality of coatings are to be appliedthe device shown with two horizontal supporting rollers 260 and 261 isbetter than a device with a single supporting roll as the two rollerconstruction provides twice as much traction and twice as much strength.The coil diameter should not vary more than plus or minus one inch fromthat originally set by the coil forming roll 50.

An example of the treatments through which the coils of the helix passaccording to Fig. 2 is the following; The first few coils coming fromthe helix forming device rotate outside the bath structure. Thence thecoil passes Patented Dec. 29 1959' through baths 70-80. Bath 70 is acleaning bath containing, for example, an aqueous solution of sodiumphosphate. Baths 71, 73, 75, 78 and 80 are water rinsing baths oneoccurring between each two consecutive chemical baths. Bath 72 may behot sulfuric acid bath. Bath 74 is another cleaning bath and bath 76 maybe a polarizing or flash plating bath. The copper is plated in bath 77,then after rinsing in bath 78 the zinc is continuously plated onto thecopper plated wire. The product thus produced may be drawn down to thesize desired with conventional wire drawing devices.

Fig. 1A shows a core wire 10 similar to that shown in Fig. l but havinga nickel layer 103 of /2 to 5% by weight between the copper layer 101and the zinc layer 102.

Example 1 A steel wire core of A diameter, for example, having a carboncontent of .10 to 60% is provided. Such a wire has a conductivity of9-1l% of the conductivity of pure copper wire of the same size. Thiswire is treated and electroplated by the process described above with1-10% (10 to 100 g. per kilo) by weight of pure copper. This layer ofcopper increases the conductivity of the steel wire by 1-10% to providea wire with a resultant conductivity of 11-20% of a pure copper wire ofthe same size. A relatively thick layer of zinc is then electroplatedonto the copper coated wire. Approximately 0.80 oz. (which representsabout 5% by weight) to 2.4 02. (which respresents about by weight) ofzinc per square inch of surface are deposited into the copper platedwire. In a typical process a inch wire is passed at a speed of 30 to 50feet per minute in and out of a copper plating bath 100 to 150 times andin and out of a zinc plating bath 100 to 150 times. The resultant wireis drawn down to the size desired by a series of drawing steps withoutany annealing.

A standard telephone wire of B.W. gauge has a standard breaking strengthof 1213 lbs. and a maximum resistance per mile of 39.23 ohms. Wire of 12B.W. gauge made by the above process containing 50 g. per kilo of copperhas the same minimum breaking strength but has a resistance per mile ofonly 34.12 ohms. Similar improved results are noted with other gauges ofwire. For wires of the same resistance it is obvious that the product ofthe present invention is stronger than the prior art products and withstronger wires, fewer poles and less hardware are required and.fewerholes for telephone poles have to be dug.

Example 2 The wire is made as described in Example 1 except that a layerof about 36% to 5% by weight of nickel is deposited between the zinclayer and the copper layer.

, 4 This proportion of nickel forms a barrier layer which preventsalloying of the copper with the zinc during drawing, annealing, heattreating or aging of the wire product.

This application is a continuation-in-part of my US. application SerialNo. 484,405, filed January 27, 1955, now abandoned. The features andprinciples underlying the invention described above in connection withspecific exemplifications will suggest to those skilled in the art manyother modifications thereof. It is accordingly desired that the appendedclaims shall not be limited to any specific feature or details thereof.

I claim:

1. An electrical conductor wire for communication installationscomprising a composite wire with a steel core, a substantially purecopper layer of 10 to g. per kilo of the product next to said steelcore, and a layer of substantially pure zince comprising 20 to g. perkilo of the product over said copper coating.

2. The product as set forth in claim 1 in which the steel core has acarbon content of .05 to .70% by weight.

3. A process of producing a steel cored conductivity Wire comprisingproviding a steel core, plating a multiplicity of concentric layers ofcopper thereon to provide 20-100 g. per kilo of said copper, plating amultiplicity of concentric layers of zinc on the copper to provide20-150 g. per kilo of zinc over the copper.

4. An electrical conductor wire for communication installationscomprising a composite wire with a steel core of high tensile strength,a layer of substantially pure, unalloyed, copper concentricallydeposited around said core and comprising 10-100 g. per kilo of the twolayers, a concentric layer of nickel covering the copper layer andcomprising /2 to 5% by weight of the product, and a layer of unalloyedzinc covering the nickel layer and comprising 20-130 g. per kilo of theproduct.

5. A process as claimed in claim 3 comprising plating a thin barrierlayer consisting of about /2 to 5% by weight of nickel between thecopper layer and the zinc layer, and thereafter drawing the plated wire.

References Cited in the file of this patent UNITED STATES PATENTS 8,930Pratt May 4, 1852 1,096,636 Mcllroy May 12, 1914 1,691,869 Fowle Nov.13, 1928 1,970,548 Batten Oct. 19, 1931 2,002,261 Domm May 21, 19352,268,617 Pierce Jan. 6, 1942 2,296,838 Domm Sept. 29, 1942 2,307,801Pierce Jan. 12, 1943 2,323,890 Adler July 13, 1943 2,392,456 Brown Jan.8, 1946

